INFLUENCE OF APPLICATION OF BIOLOGICALLY ACTIVE WATER COMPLEX "HALPI" ON PROTEIN AND NITROGEN EXCHANGE OF ELDERLY DOGS

This article presents a study of the effect of the use of a biologically active water complex "HALPI" on protein metabolism in geriatric dogs. When assessing the effect of the biologically active water complex "HALPI" on the indicators of protein metabolism in dogs, it was found that the use of this biologically active water complex promotes an increase in the amount of total protein. in organism. Thus, the use of a biologically active water complex "HALPI" affects metabolic processes by compensating for possible deficiencies of vitamins and microelements, which contributes to the improvement of the quality of life of elderly dogs

Aerobic Bacteria Produce Nitric Oxide via Denitrification and Trigger Algal Population Collapse

Microbial interactions govern marine biogeochemistry. These interactions are generally considered to rely on exchange of organic molecules. Here we report on a novel inorganic route of microbial communication, showing that algal-bacterial interactions are mediated through inorganic nitrogen exchange. Under oxygen-rich conditions, aerobic bacteria reduce algal-secreted nitrite to nitric oxide (NO) through denitrification, a well-studied anaerobic respiration mechanism. Bacteria secrete NO, triggering a cascade in algae akin to programmed cell death. During death, algae further generate NO, thereby propagating the signal in the algal population. Eventually, the algal population collapses, similar to the sudden demise of oceanic algal blooms. Our study suggests that the exchange of denitrification intermediates, particularly in oxygenated environments, is an overlooked yet ecologically significant route of microbial communication within and across kingdoms.

Hydrogeochemistry Studies in the Oil Sands Region to Investigate the Role of Terrain Connectivity in Nitrogen Critical Loads

Hydrology and geochemistry studies were conducted in the Athabasca Oil Sands region to better understand the water and nitrogen cycles at two selected sites in order to assess the potential for nitrogen transport between adjacent terrain units. A bog—poor fen—upland system was instrumented near Mariana Lakes (ML) (55.899° N, 112.090° W) and a rich fen—upland system was instrumented at JPH (57.122° N, 111.444° W), 100 km south and 45 km north of Fort McMurray, Alberta respectively. LiDAR surveys were initially conducted to delineate the watershed boundaries and topography and to select a range of specific locations for the installation of water table wells and groundwater piezometers. Field work, which included a range of physical measurements as well as water sampling for geochemical and isotopic characterization, was carried out mainly during the thaw seasons of 2011 to 2015. From analysis of the runoff response and nitrogen species abundances we estimate that nitrogen exchange between the wetlands and adjacent terrain units ranged between 2.2 and −3.1 kg/ha/year for rich fens, 0.6 to −1.1 kg/ha/year for poor fens, and between 0.6 and −2.5 kg/ha/year for bogs, predominantly via surface pathways and in the form of dissolved nitrate. A significant storage of dissolved ammonium (and also dissolved organic nitrogen) was found within the pore water of the bog-fen complex at Mariana Lakes, which we attribute to decomposition, although it is likely immobile under current hydrologic conditions, as suggested by tritium distributions. In comparison with the experimental loads of between 5 and 25 kg/ha/year, the potential nitrogen exchange with adjacent terrain units is expected to have only a minor or negligible influence, and is therefore of secondary importance for defining critical loads across the regional landscape. Climate change and development impacts may lead to significant mobilization of nitrogen storages, although more research is required to quantify the potential effects on local ecosystems.

COMPLEX EFFECT OF CHROME AND SALINATION ON NITROGEN EXCHANGE IN PUMPKIN PLANTS

A specific character of physiological-biochemical stress responses of pumpkin plants to toxic effect of cadmium under conditions of salinity in the course of their long-term cross-adaptation was investigated. Cr and NaCl were added either alone or in combination in Knop solution along with non-treated controls. In 7- and 14- day plants, all the physiological processes studied (shoot and root growth, bioaccumulation of fresh and dry biomass by them and nitrogen-protein metabolism in different plant organs) were found to be more sensitive to inhibitory action of Cr excess than to NaCl effect. However, in 21-day plants, especially in their roots, a some activation of growth and biosynthetic processes was observed in the presence of combined Cr and NaCl treatments than at their lone application. All this indicates that an adaptation of plants to salinity is accompanied by a some reduction in toxic effect of Cr on growth and metabolism of plants

Measurement report: Nitrogen isotopes (δ¹⁵N) and first quantification of oxygen isotope anomalies (Δ¹⁷O, δ¹⁸O) in atmospheric nitrogen dioxide

The isotopic composition of nitrogen and oxygen in nitrogen dioxide (NO2) potentially carries a wealth of information about the dynamics of the nitrogen oxides (NOx = nitric oxide(NO) + NO2) chemistry in the atmosphere. While nitrogen isotopes of NO2 are subtle indicators of emissions, NOx chemistry and isotopic nitrogen exchange between NO and NO2, oxygen isotopes are believed to reflect only the O3/NOx/VOC chemical regime in different atmospheric environments. In order to access this potential tracer of the tropospheric chemistry, we have developed an efficient active method to trap atmospheric NO2 on denuder tubes and measured, for the first time, its multi-isotopic composition (δ15N, δ18O, and Δ17O). The δ15N values of NO2 trapped at our site in Grenoble, France, show little variability (−11.8 to −4.9 ‰) with negligible N isotope fractionations between NO and NO2 due to high NO2/NOx ratios. NOx emissions main sources are estimated using a stable isotope model indicating the predominance of traffic NOx emissions in this area. The Δ17O values, however, reveal an important diurnal cycle peaking in late morning at (39.2 ± 1.7) ‰ and decreasing at night until (20.5 ± 1.7) ‰. On top of this diurnal cycle, Δ17O also has substantial variability during the day (from 29.7 to 39.2 ‰), certainly driven by changes in the O3 to peroxyl radicals ratio. The night-time decay of Δ17O(NO2) appears to be driven by NO2 slow removal, mostly from conversion into N2O5, and its formation from the reaction between O3 and emitted NO. Our Δ17O(NO2) measured towards the end of the night is quantitatively consistent with typical values of Δ17O(O3). These preliminary results are very promising for using Δ17O of NO2 as a probe of the atmospheric oxidative activity and for interpreting NO3− isotopic composition records.

Evolution and Preservation of Venous Gas Emboli at Alternating High and Moderate Altitude Exposures

INTRODUCTION: The evolution and preservation of venous gas emboli (VGE), as markers of decompression stress, were investigated during alternating high- and moderate altitude exposures, thus, simulating a fighter aircraft high-altitude flight, interrupted by refueling excursions to lower altitudes.METHODS: Eight men served as subjects during three normoxic simulated altitude exposures: High = 90 min at 24,000 ft; High-Low = three × 30 min at 24,000 ft, interspersed by two 30-min intervals at 15,000 ft; Low = 90 min at 15,000 ft. VGE scores were assessed by cardiac ultrasound, using a 5-grade scale. Respiratory nitrogen exchange was measured continuously using a modified closed-circuit electronic rebreather.RESULTS: Both High and High-Low induced persistent VGE, with no inter-condition difference either at rest [median (range): High: 1 (0-3), High-Low: 2 (0-3)] or during unloaded knee-bends [High: 3 (1-4), High-Low: 3 (0-4)], whereas VGE was considerably less in Low, both at rest [0 (0-1)] and during knee-bends [0 (0-2)]. In High-Low, VGE decreased temporarily during the 15,000-ft excursions, but resumed pre-excursion values upon return to 24,000 ft. During the final descent to ground level, VGE were more persistent following High-Low than High. In both High and Low, nitrogen was continuously washed out at altitude, whereas in High-Low, the washout at 24,000 ft was interrupted by nitrogen uptake at 15,000 ft.DISCUSSION: In normoxic conditions, long-duration flying at a cabin altitude of 24,000 ft is associated with substantial VGE occurrence, which is not abolished by intermittent excursions to a cabin altitude of 15,000 ft.Ånell R, Grönkvist M, Gennser M, Eiken O. Evolution and preservation of venous gas emboli at alternating high and moderate altitude exposures. Aerosp Med Hum Perform. 2020; 91(1):11–17.